Disc drive suspension

ABSTRACT

A suspension comprises a base plate, a load beam, and a hinge member. An extending portion is provided on the side of the hinge member. A step forming portion is formed between the base plate mounting portion and the extending portion. The step forming portion has a difference in level such that the extending portion is situated inside the base plate mounting portion with respect to its thickness direction. An end portion of the flexure fixed on the extending portion is situated inside the surface of the base plate mounting portion with respect to the thickness direction.

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] The present application is a Continuation of U.S. applicationSer. No. 10/161,813 filed Jun. 4, 2002, which is based upon and claimsthe benefit of priority from the prior Japanese Patent Application No.2001-374533, filed Dec. 7, 2001, the entire contents of which areincorporated herein by reference.

BACKGROUND OF THE INVENTION

[0002] 1. Field of the Invention

[0003] The present invention relates to a disc drive suspensionincorporated in an information processing apparatus such as a personalcomputer.

[0004] 2. Description of the Related Art

[0005]FIG. 14 shows a part of a hard disc drive (HDD). This disc drivecomprises suspensions 3 and actuator arms 4 on which the suspensions 3are mounted, individually. Each suspension 3 supports a magnetic headportion 2 for recording on or reading information from the recordingsurface of a disc 1 for use as a recording medium. The actuator arms 4can be turned around a shaft (not shown) by means of a positioning motor(not shown).

[0006] Each suspension 3 is provided with a base plate 5, a load beam 6extending from the base plate 5 toward the head portion 2, a flexure 7,etc. A proximal portion 6 a of the load beam 6 is lapped and fixed onone surface 5 a of the base plate 5 with respect to its thicknessdirection. The flexure 7 is fixed on the load beam 6 by laser welding. Aslider 8 that constitutes the head portion 2 is mounted on the distalend portion of the flexure 7.

[0007] The flexure 7 that is provided with a wiring portion that extendsalong the load beam 6 from the head portion 2 toward the base plate 5.An end portion of the flexure 7 is fixed to an extending portion (notshown) that projects sideways from the proximal portion 6 a of the loadbeam 6. External lead wires are connected (or bonded) to electrode padson the end portion of the flexure 7.

[0008] As a means of fixing the base plate 5 on the actuator arm 4, aboss portion is proposed such that it is caulked on the base plate 5, asshown in FIG. 14. More specifically, a support jig (not shown) isinserted into the respective base plates 5 of each two adjacentsuspensions 3, and the boss portion of each base plate 5 supported bymeans of the support jig is caulked.

[0009] In a suspension proposed as an alternative form, a proximalportion 6 a of a load beam 6 is lapped and fixed on the other surface 5b of a base plate 5. In the case of the suspension of this type, theproximal portion 6 a of the load beam 6 may be also provided with anextending portion on which an end portion of a wired flexure 7 is fixed.

[0010] If the extending portion and the proximal portion 6 a of the loadbeam 6 are flush with each other, however, the end portion of the wiredflexure that is fixed on the extending portion inevitably projectsoutward in the thickness direction of the base plate 5. Thus, there is adanger of the support jig interfering with the end portion of theflexure.

BRIEF SUMMARY OF THE INVENTION

[0011] Accordingly, the object of the present invention is to provide adisc drive suspension capable of avoiding interference between an endportion of a flexure and a jig or the like.

[0012] According to a first aspect of the present invention, a stepforming portion with a difference in level in its thickness direction isformed by press molding or the like between a base plate mountingportion and an extending portion that is formed on the side of a loadbeam, a flexure, or a hinge member. According to this disc drivesuspension, the flexure that is fixed on the extending portion can beprevented from interfering with a jig for fixing the base plate or thelike. Further, the step forming portion serves to enhance the bendingstiffness of the extending portion and its surroundings.

[0013] Preferably, the step forming portion has a difference in level toensure the flexure fixed on the extending portion is not situated on theextension of the surface of the base plate mounting portion. Accordingto this configuration, a wiring portion or the like of the flexure thatis fixed on the extending portion of the hinge member can be preventedfrom interfering with the jig or the like.

[0014] In the present invention, an end portion of the flexure mayextend rearward from the base plate mounting portion. According to thisconfiguration, an intermediate portion of the flexure with respect toits longitudinal direction can be fixed on the extending portion.

[0015] According to a second aspect of the invention, there is provideda suspension that comprises an extending portion protruding sidewaysfrom a proximal portion of a load beam, and in which a step formingportion is formed between the proximal portion of the load beam and theextending portion. According to this invention, the step forming portionthat is formed between the proximal portion of the load beam and theextending portion serves to prevent the flexure on the extending portionfrom interfering with the jig or the like. The step forming portion alsoserves to enhance the bending stiffness of the extending portion and itssurroundings.

[0016] Preferably, in the present invention, the step forming portionhas a difference in level to ensure the wired flexure fixed on theextending portion is not situated on the extension of the surface of theproximal portion. According to this configuration, a wiring portion ofthe wired flexure that is fixed on the extending portion of the loadbeam can be prevented from interfering with the jig or the like.

[0017] Additional objects and advantages of the invention will be setforth in the description which follows, and in part will be obvious fromthe description, or may be learned by practice of the invention. Theobjects and advantages of the invention may be realized and obtained bymeans of the instrumentalities and combinations particularly pointed outhereinafter.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0018] The accompanying drawings, which are incorporated in andconstitute a part of the specification, illustrate presently preferredembodiments of the invention, and together with the general descriptiongiven above and the detailed description of the embodiments given below,serve to explain the principles of the invention.

[0019]FIG. 1 is a plan view of a disc drive suspension according to afirst embodiment of the invention;

[0020]FIG. 2 is a sectional view of the suspension taken along lineF2-F2 of FIG. 1;

[0021]FIG. 3 is a side view of a part of the suspension taken in thedirection of arrow F3 of FIG. 1;

[0022]FIG. 4 is a sectional view of a part of a disc drive provided withthe suspension shown in FIG. 1;

[0023]FIG. 5 is a plan view of a load beam of the suspension shown inFIG. 1;

[0024]FIG. 6 is a plan view of a base plate of the suspension shown inFIG. 1;

[0025]FIG. 7 is a plan view of a hinge member of the suspension shown inFIG. 1;

[0026]FIG. 8 is a plan view of a flexure of the suspension shown in FIG.1;

[0027]FIG. 9 is a plan view of a disc drive suspension according to asecond embodiment of the invention;

[0028]FIG. 10 is a plan view of a disc drive suspension according to athird embodiment of the invention;

[0029]FIG. 11 is a plan view of a disc drive suspension according to afourth embodiment of the invention;

[0030]FIG. 12 is a plan view of a disc drive suspension according to afifth embodiment of the invention;

[0031]FIG. 13 is a plan view of a disc drive suspension according to asixth embodiment of the invention; and

[0032]FIG. 14 is a sectional view of a part of a hard disc driveprovided with conventional suspensions.

DETAILED DESCRIPTION OF THE INVENTION

[0033] A first embodiment of the present invention will now be describedwith reference to FIGS. 1 to 8.

[0034] A hard disc drive (HDD) 10 shown in FIG. 4 comprises a pluralityof discs 11 for use as recording media, a plurality of suspensions 13each having a head portion 12 for magnetically recording information onor reading it from the recording surface of each disc 11, actuator arms14, etc. Each actuator arm 14 is an example of an arm member to befitted with each suspension 13, and can be turned around a shaft (notshown) by means of a positioning motor (not shown).

[0035] As shown in FIG. 1, each suspension 13 includes a load beam 20, abase plate 21, a hinge member 22, a wired flexure 23, etc.

[0036] As shown in FIG. 5, the load beam 20 has a proximal portion 30and a distal end portion 31, and a dimple 32 is formed on the distal endportion 31.

[0037] As shown in FIG. 6, a cylindrical boss portion 35 having acircular hole 35 a is formed on the base plate 21. The boss portion 35is inserted into a mounting hole 36 (shown in FIG. 4) in the actuatorarm 14. The base plate 21 is fixed to the actuator arm 14 in a mannersuch that the boss portion 35 is caulked (or plastically deformed) frominside.

[0038] As shown in FIGS. 1 and 7, the hinge member 22 has an end portion40 lapped and fixed on the proximal portion 30 of the load beam 20,flexible portions 42 formed individually on the opposite sides of anopening 41 and elastically deformable in its thickness direction, a baseplate mounting portion 43 lapped and fixed on the base plate 21, and anextending portion 44 extending sideways from the mounting portion 43.

[0039] As shown in FIGS. 2 and 3, a step forming portion 45 is formedbetween the extending portion 44 of the hinge member 22 and the baseplate mounting portion 43 by press working. The step forming portion 45has a difference in level such that the extending portion 44 is situatedinside a surface 43 a of the base plate mounting portion 43 with respectto the thickness direction (or in a region indicated by arrow S in FIG.2).

[0040] As shown in FIG. 8, the flexure 23 has a metal base 50 formed ofa metal sheet as an example of a material that is thinner than the loadbeam 20 and a wiring portion 51 including a conductive layer 53 that isformed over the surface of the metal base 50 with an electricalinsulating layer 52 between them. Thus, the flexure 23 is a so-calledwired flexure. The metal base 50 is formed of a springy stainless-steelsheet with a thickness of about 18 μm to 30 μm, for example. The flexure23 extends along the load beam 20.

[0041] A tongue portion 56 that serves as a movable portion andoutrigger portions 57 and 58 are formed on a distal end portion 55 ofthe flexure 23. The outrigger portions 57 and 58 are situatedindividually on the opposite sides, left and right, of the tongueportion 56. The tongue portion 56 and the outrigger portions 57 and 58can bend in the thickness direction of the flexure 23. The tongueportion 56 engages a dimple 32 on the distal end portion 31 of the loadbeam 20. A slider 59 (shown in FIG. 4) is mounted on the tongue portion56. The slider 59 is provided with a transducer (not shown) for use as amagneto-electric conversion element. The transducer, slider 59, etc.constitute the head portion 12.

[0042] Electrode pads 66 are provided on the other end portion 65 of theflexure 23. External lead wires (not shown) are connected to theelectrode pads 66. The end portion 65 is lapped and fixed on theextending portion 44 of the hinge member 22. A first intermediateportion 67 that is lapped on the load beam 20 and a belt-shaped secondintermediate portion 68 off the load beam 20 are formed between thedistal end portion 55 and the other end portion 65 of the flexure 23.

[0043] The end portion 65 of the flexure 23 is fixed in a predeterminedposition on the extending portion 44 of the hinge member 22 by laserwelding or adhesive bonding. The extending portion 44 of the hingemember 22 is formed having holes 73 and 74 in which positioning pins 71and 72 (indicated by a two-dot chain line) can be inserted,respectively. The end portion 65 of the flexure 23 is also formed havingholes 80 and 81 for the insertion of the positioning pins 71 and 72.These pins 71 and 72 are provided on the body of a positioning tool (notshown).

[0044] As shown in FIG. 4, a gap G that is wide enough to allow theinsertion of a support jig J is defined between the respective hingemembers 22 of each two adjacent suspensions 13 on the actuator arms 14.In fixing each base plate 21 on its corresponding actuator arm 14, thehinge member 22 is supported by means of the support jig J. In thisstate, the boss portion 35 is plastically deformed in a manner such thatit is pressurized from inside by pressing a caulking part, such as asteel ball larger in diameter than the hole 35 a of the boss portion 35,into the hole 35 a. By doing this, the base plate 21 can be fixed on theactuator arm 14.

[0045] In each suspension 13, the step forming portion 45 is formedbetween the base plate mounting portion 43 and the extending portion 44of the hinge member 22. The end portion 65 of the flexure 23 is recessedinside the surface of the base plate mounting portion 43 in thethickness direction. As the support jig J is inserted into the gap G,therefore, there is no possibility of its interfering with the endportion 65 of the flexure 23. Further, the support jig J can beprevented from interfering with the wiring portion 51 or the electrodepads 66.

[0046] The step forming portion 45 serves to enhance the stiffness ofthe extending portion 44 and its surroundings. If the extending portion44 touches any object during the assembly of the suspension 13 or thelike, therefore, it can be restrained from being deformed.

[0047] As shown in FIG. 2, the end portion 65 of the flexure 23 or theelectrode pads 66 is situated within the region S inside the surface 43aof the base plate mounting portion 43 with respect to the thicknessdirection. Thus, the overall thickness of the suspension can be madesmaller than in the case where the step forming portion 45 is notformed. If the step forming portion 45 is not formed, the end portion 65of the flexure 23 projects outward in the thickness direction of thehinge member 22. The overall thickness of the suspension describedherein is a thickness that covers the base plate 21 and the end portion65 of the flexure 23.

[0048]FIG. 9 shows a suspension 13A according to a second embodiment ofthe invention. A slit 22 a is formed in an end portion 40 of a hingemember 22 of the suspension 13A. It extends in the longitudinaldirection of the hinge member 22 and opens into an opening 41. Couplingportions 22 b and 22 c that connect with a load beam 20 are formed onthe opposite sides of the slit 22 a, individually. A part of a flexure23 passes through the slit 22 a in the longitudinal direction.

[0049] The hinge member 22 of the suspension 13A is formed having anextending portion 44 and a step forming portion 45, which are similar tothose of the suspension 13 of the first embodiment. An end portion 65 ofthe flexure 23 is lapped and fixed on the extending portion 44. A partof the flexure 23 passes through the slit 22 a in the longitudinaldirection, and extends from a base plate mounting portion 43 toward theextending portion 44. Since the suspension 13A shares otherconfigurations with the suspension 13 shown in FIG. 1, common numeralsare used to designate portions that are common to the two suspensions,and a repeated description of those common portions is omitted.

[0050]FIG. 10 shows a suspension 13B according to a third embodiment ofthe invention. A hinge member 22 of the suspension 13B is formed havingan extending portion 44 and a step forming portion 45, which are similarto those of the suspension 13 of the first embodiment. A flexure 23 ofthe suspension 13B has an intermediate portion 100 to be lapped on theextending portion 44. The intermediate portion 100 is fixed on theextending portion 44. An end portion 65 of the flexure 23 or electrodepads 66 extends rearward from the hinge member 22. Since the suspension13B shares other configurations with the suspension 13A shown in FIG. 9,common numerals are used to designate portions that are common to thetwo suspensions, and a repeated description of those common portions isomitted.

[0051]FIG. 11 shows a suspension 13C according to a fourth embodiment ofthe invention. A flexure 23 of the suspension 13C has a base platemounting portion 43′ that overlaps a base plate 21 in its intermediateportion with respect to its longitudinal direction. An extending portion44′ and a step forming portion 45′ are formed on the base plate mountingportion 43′. The step forming portion 45′, like the step forming portion45 shown in FIG. 2, has a difference in level. Since the suspension 13Cshares other configurations with the suspension 13B shown in FIG. 10,common numerals are used to designate portions that are common to thetwo suspensions, and a repeated description of those common portions isomitted.

[0052]FIG. 12 shows a suspension 13D according to a fifth embodiment ofthe invention. A load beam 20 of the suspension 13D has a base platemounting portion 20 a that is situated on the side of a base plate 21with respect to an opening 41 and a distal end portion 20 b on the sideof a head portion 12. The base plate 21 having a circular shape is fixedon the base plate mounting portion 20 a of the load beam 20. Anextending portion 44 d and a step forming portion 45 d are formed on thebase plate mounting portion 20 a. Positioning holes 73 d and 74 d areformed in the extending portion 44 d.

[0053] The step forming portion 45 d on the load beam 20, like the stepforming portion 45 shown in FIG. 2, has a difference in level. Since thesuspension 13D shares other configurations with the suspension 13B shownin FIG. 10, common numerals are used to designate portions that arecommon to the two suspensions, and a repeated description of thosecommon portions is omitted.

[0054]FIG. 13 shows a suspension 13′ according to a sixth embodiment ofthe invention. In the suspension 13′, a base plate 21 is lapped andfixed on a proximal portion 30 of a load beam 20. An extending portion90 protrudes sideways from the proximal portion 30. A step formingportion 91 is formed between the proximal portion 30 and the extendingportion 90. An end portion 65 of a wired flexure 23 is lapped and fixedon the extending portion 90 by laser welding or with an adhesive agent.

[0055] The step forming portion 91 is given a difference in level bypress working to ensure the end portion 65 of the flexure 23 is notsituated on the extension of the surface of the proximal portion 30 ofthe load beam 20. Positioning holes 73 and 74, which resemble the onesaccording to the first embodiment, are formed in the extending portion90. Positioning holes 80 and 81 are also formed in the end portion 65 ofthe flexure 23. Since the suspension 13′ shares other configurations andeffects with the suspension 13 of the first embodiment, common numeralsare used to designate portions that are common to the two suspensions,and a repeated description of those common portions is omitted.

[0056] In carrying out the present invention, it is to be understoodthat the components of the invention, including the position and shapesof the extending portion and the step forming portion, as well as thespecific forms of the load beam, hinge member, and flexure, may bevariously changed and modified without departing from the scope orspirit of the invention.

[0057] Additional advantages and modifications will readily occur tothose skilled in the art. Therefore, the invention in its broaderaspects is not limited to the specific details and representativeembodiments shown and described herein. Accordingly, variousmodifications may be made without departing from the spirit or scope ofthe general inventive concept as defined by the appended claims andtheir equivalents.

What is claimed is:
 1. A disc drive suspension comprising: a base plate;a load beam having a proximal portion with the base plate fixed thereonand a distal end portion; a flexure fixed on the load beam and having ahead portion thereon; an extending portion provided on a side of theproximal portion of the load beam and having a part of the flexure fixedthereon; and a step forming portion formed between the extending portionand the proximal portion.
 2. A suspension according to claim 1, whereinsaid step forming portion has a difference in level to ensure theflexure fixed on the extending portion is not situated on the extensionof the surface of the proximal portion.